WASHINGTON - In a stunning last-minute announcement, FBI director James Comey said Sunday that his agency's review of newly discovered emails has not changed his earlier conclusion that Democratic presidential nominee Hillary Clinton should not be prosecuted for her handling of classified information over email as secretary of State.

In a letter to lawmakers, Comey said the FBI is standing by its original findings made in July.

"The FBI investigative team has been working around the clock to process and review a large volume of emails from a device obtained in connection with an unrelated criminal investigation," Comey said in the letter. "During that process we reviewed all of the communications that were to or from Hillary Clinton while she was secretary of State," Comey wrote. "Based on our review, we have not changed our conclusions that we expressed in July with respect to Secretary Clinton."

Comey had rocked the presidential race with his announcement Oct. 28 that the FBI had uncovered a new trove of emails that might be relevant to the investigation of Clinton's use of a private email server. The emails were discovered on the computer of Anthony Weiner, the estranged husband of Clinton aide Huma Abedin.

The announcement, as voters prepare to head to the polls Tuesday, added more drama to an already turbulent campaign season.

Clinton was en route to Cleveland on Sunday when Comey issued his letter.

Aboard her plane, aides were seen sharing the letter on their wireless devices. Clinton communications director Jennifer Palmieri came to the back of the plane where the press is seated.

“We are glad to see that he has found -- and we were confident that he would -- that he has confirmed the conclusion he reached in July; and we’re glad that this matter is resolved,” she told reporters.

The campaign appeared to signify it would not gloat over the announcement, as Palmieri declined to answer questions as she customarily does.

Clinton’s commanding 11-point lead after the final debate with Republican Donald Trump in Las Vegas has narrowed to four to five points nationally in the aftermath of the late October announcement. She’s seen Trump close in on her in states like New Hampshire and North Carolina, where she’d once enjoyed a comfortable lead.

Though there is no way to tell how much of that is related to the announcement — versus a natural tightening of the race — the campaign has privately worried that the surprise announcement would badly hurt their attempts to court Republicans disillusioned with Trump.

Campaigning in Minnesota, Trump did not specifically mention Comey's announcement but appeared to allude to it.

Clinton is "protected by a rigged system," he said. "She shouldn't be allowed to run for president."

Comey’s brief written notice to Congress Sunday was issued after consultation with Attorney General Loretta Lynch, a federal law enforcement official said Sunday.

The official who is not authorized to comment publicly said both sides agreed on the conclusion, which was reached earlier Sunday. The official said the investigative team that conducted the initial inquiry into Clinton’s handling of classified information as secretary of State worked night and day to review hundreds of thousands of communications as part of the new review.

The official said many of the communications involved in the new review were duplicates of emails analyzed during the initial inquiry.

The team delivered its findings Sunday, the official said.

As recently as Friday, federal authorities said that the work involved in the review had made it increasingly unlikely that it could be completed by Election Day.